How a barrel is indicated in the lathe is crucial to a quality thread job. There are many different methods of indicating barrels used by other gunsmiths such as using bushings, gauge pins, indicating rods, etc. These methods can all negatively affect your indicator reading because of stacked tolerances or improperly fitting bushings or gauge pins. Because of this, we indicate all of our barrels with special indicators that allow us to reach inside the bore and read directly off the lands and grooves of the barrel. This allows us to remove any variables other methods may have and indicate our barrels as close to zero runout as possible. Before threading, barrels are indicated to under .0002” TIR. For reference, that is approximately 1/10th the diameter of an average human hair (~.002”).
After indication, barrels are turned down to specified dimensions for the desired thread and single-point threaded to Class 3A specifications using high quality carbide tooling. We measure every single barrel with a thread pitch micrometer to ensure that our muzzle threads are properly sized and will be compatible with all muzzle devices.
Q recommends miminum barrel dimensions of .610" for 1/2"-28 and .735" for 5/8"-24.
Sig/Q Taper Muzzle Threading
Muzzle Threading with a 25 degree "Sig/Q Taper"
Solid work holding is crucial to precision machining processes. Failure to achieve this can lead to many issues including misaligned threads which can result in severe damage to suppressors and muzzle devices. We have developed processes that minimize the chance of damage to your barrel finish, however, there is a chance your barrel finish WILL be cosmetically scratched or marked during the threading process. There is no way around this possibility and Diamond C Precision will NOT be responsible for any cosmetic damages.
